The present invention relates to multicylinder petrol engines provided with a system for variable actuation of the valves.
The applicant has already proposed, in its U.S. Pat. No. 6,237,551, an internal-combustion engine of the type comprising:                at least one intake valve and at least one exhaust valve for each cylinder, each valve being provided with respective elastic return means, which push the valve towards a closed position for controlling respective intake and exhaust pipes; and        at least one camshaft, for actuating the intake and exhaust valves of the engine cylinders by means of respective tappets;        in which each intake valve is controlled by the respective tappet against the action of the aforesaid elastic return means by interposition of hydraulic means that include a pressurized fluid chamber;        said pressurized fluid chamber being designed to be connected by means of a solenoid valve to an exhaust channel in order to uncouple the valve from the respective tappet and bring about fast closing of the valve as a result of the respective elastic return means;        electronic control means for controlling each solenoid valve so as to vary the time and the opening stroke of the respective intake valve according to one or more operating parameters of the engine.        